Sand blasting stencil



June 13, 1939. c. E. FRlcK i 2,162,332

SANDBLASTING sTENcIL Filed Oct. 28, 1937 I A u,

55 orkfthat is, t

J The invention consistsin the several Patented June 1 3, 1939 PATENT ofi-Fics SAND BLASTING STENCIL Carl E. Frick, Chicago. lli., assignor, by mesne assignments, to Van Cleef Bros., Chicago, Ill., 'a partnership consisting of Noah Van Cleef,

Felix van Cleef, and Paul Van Cieef Application October 28,v

1931, serial No; 171,452.

s claims. (ci. 41-39) The present invention relates generally to stencils for use in'cutting letters, symbols, or designs on monument-forming stones or stonework by wayof sandblasting. Moreparticularly the in vention relates to that type of stencil which Acomprises a sheet of sand resistant material and a coating of adhesive on the back face of the sheet, is adapted after application to the surface to\be cut to have the desiredletters, symbols or desi n's marked or penciled on the front face thereof a d then cut out or removed by a knife or like sharp instrument, and vserves in connection with the cutting operation,4 that is, when sand is blasted/ thereagainst in connection with cutting 'of the surface. to control the sand so that it encounters only the portions of the surface behind the cut outs and hencecuts by its abrasive action the desired letters, symbols or. designs in the surface.

. One object of the present invention is to provideastencil of this type which; is more efficient and practical vthan previously designed Vstencils Y of the same general character and also due to' the character or composition of the sand resistant sheetis adapted to make sharper or better defined letters and has materially greater wearing or lasting properties. l

Another object of the invention is'to provide a stencil of the type u nder consideration in which the sand resistant sheet is formed or composed -36 of vulcanizedrubber and an admixture of glue to the end that the sheet as a whole is notl too elastic andnot4 only can be cut readilyfln connection with the formation of the desired letters'.4 symbols or designs thereinbut also possesses the necessary or proper amount of durability to withstand heavy sand blasting.

Another object of the invention is to provide a stencil of' the type and character under consideration in which the coating' on the back face of the sheetf sand resistant material is in the form of a rubber base pressure sensitive adhesive and no only permits the sheet to be applied readily o the surface to be cut but in addition rorms/ the sand against the sheet.

A further object of the invention islto prov vide a sand blasting Jstencil which is generallyl of new' and impr ved design and maybemanutecti'ng the Dr hesive coating n theback of the sand resistant .sheet-prior to ppucauon ofV the sneeuw the surface to be cut.

ithe invention and the various acteristics of the presepi-, xl

4`C )ther objects advantages andy stencil will be a factured at 'a low and reasonable cost in addition has-or embodies a holland sheet for pro sure sensitive rubber base'adp rent from a consideration of l the. fdllo'wing'detailed description.

novel-feng tures which are hereinafter set forth and are more particularly defined by claimsV at the conclusion hereof.

In the drawing which accompanies and formsv a part of this specification or disclosure and in which llike numerals of reference denote corresponding parts'throughout the several views:

Figure 1 isa perspective of a monument-forming stone having applied to the front .face thereof a stencilembodying the invention;

Figure 2 is a. perspective showing the stencil before stripping or peeling of the hollandv sheet from the coating of pressure sensitive rubber base adhesive in connection With\ application oi' the sand resistart sheet to the Work;

Figure 3 is a fragmentary .perspective of the holland sheet over which the sheetforming material is calendered or spread in connection with fabrication of the stencil;v

Figure 4 is a fragmentary perspective showing the holland sheet of Figure 3'with thesheet formingmaterial calc ndered or v4spread thereover; f

Figure 5 is a fragmentary perspectiveshowing the holland sheet and sand resisting sheet after the vulcanizing operation and withthe coating of pressure sensitive rubber base adhesive on resistant sheet; Figure 6 is a fragmentary perspective view showing the original holland sheet, the sand resistant'sheet, and the coating of pressure sensi- -tive rubber base adhesive after applicationvoi The stencil which is shown in the drawing conf stitutes the preferred embodiment of the in' the exposed face, that is, the back face of a sand vention. It is shown or illustrated in connection .with a monument-forming stone Sv and serves. as hereinafter described to control a sand blast in connection with the cutting ror formation of letters, symbols, or designs on the stone. As shown in Figure 8, the stencil embodies as. the principle parts or elements thereof a sheet 9, a coating ill onthe baclrface4 of thesheet 9, and

av protective sheetil of holland for 'the coating4 IG. The coating lil, as hereinafter described, is formed of pressure sensitive rubber base adhesive and is adapted, sheet Il to secure the sheet` 9 in place on the stone "S, The sheet 9, is formed of sand resistant material and' Aadapted when the stencil is' in place on thestone to have the desired letters, '.symbols, or designs penciled thereon andthen cut out orremoved from' it by a knife or similar sharp fter removal fthe holland- Ingredients Pounds Ounces Smoked rubber sheets (hard tough plantation type mbber) Whiting I coeSwS capaces' In connection with fabrication of the stencil the `aforementioned ingredients are properly milled and mixed together and then while in the form of a plastic mass are calendered or otherwise spread over a sheet` I2 of holland. Preferably the mass isl spread over the rsheet I2 until it has a thickness of approximately .045 inch. 'I'he Whiting content of the sheet forming material acts -as a stiffener and a ,filler and the petrolatum serves as a dispersing or softening agent and to make the mass more workable. The

sulfur constitutes the vulcanizing agent for the rubber and the tetramethyl-thiuram disulphide operates as anaccelerator for the vulcanizing agent. The zinc oxide content of the material serves to activate the accelerator, that is, the

tetramethyl-thiuram disulphide, and the pearl.

glue operates to toughen the mass or material as a whole and also to harden or reduce the `elasticity of the rubber.l After the calendering or spreading operation the holland sheet I2 with the layerv of sheet'forming material thereon is placed in an oven or like heating apparatus for a period of 18 hours and subjected to a temperature of approximately 200 F. This serves to vulcanize the rubber content of the material and results in formation of the sheet 9. Due to the fact that the latter lis composed of vulcanized rubber and an admixture of glue it is .net .only extremely tough.-.a.nd durable but also sand re sistant and substantially inelastic. The adhesive coating I 9 is applied to the exposed face of the sand vresistant sheet 9 by way of a calendering or spreading operation after the vulcanizing step. It is essentiallyperman'ently tacky and preferably is formed-of the following ingredients in substantially the proportions specified:

Ingredients Pounds Ounces Milled white crepe rubber 38 0 Zinc oxide l2 0 Betgundy pitch 16 l2 Oregon balsem 1 8 The Burgundy pitch content of 'the adhesive serves as a softener and makes the adhesive exsponds in' size to the coating II and serves to prevent thalatter from adhering to objects prior to use of the stencil. During or after application of the holland sheet II to the pressure sensitive rubber base adhesive I9 the holland sheet I2 is removed from the front face of the sand resistant sheet 9. Upon removal of the sheet I2 a ne layer I3 of talc is applied to the exposed or front face of the sheet 9 by way of dusting. 'I'he talc layer I3 prevents the sheetA 9 from having any adhesive tendencies and permits the stencil to be rolled Without any likelihood of the exposed or front face of the sheet 9 adhering to the exposed face of the holland sheet Il. In addition it forms 'a smoothv surface or facing on which the letters or symbols to be cut may be readily marked. The holland sheet I2 on which the Sand resistant sheet 9 is formed serves as a/backing for the sheet forming material and also to permit the material to be readily handled at the conof the fact that the coating I0 is in the form of .a permanently tacky pressure sensitive rubber clusion of the vulcanizing operation. By reason base adhesive the stencil may be readily applied firmly held in place against the work during the' sand blasting operation.-

In using the stencil in connection with sandA blasting to form letters on the stone S the holland sheet IIis first stripped or peeled from the coating Ill of pressure sensitive rubber base adhesive.

Thereafter the stencil is pressed yagainst the surface to be cut or letteredin order to bring. the coating g I0 into adhesively connected relation with the latter. Thereafter the letters to be cut in the stone S are penciled or otherwise marked on the talced front face of the sheet 9 and are cut out or removed by a sharp'knife or like tool. At the conclusion of this operation or step sand is blasted` against the sheet 9. During the sand blasting operation the sheet controls the `sand so thatit encounters only the portions of the surface of the stone S behind the cut outs and hence cuts by its abrasive action the desired -letters in the surface. By reason of the fact that the sheet ber and glue it resists any abrasive/or wearing effect of the sand and hence the portions thereof 19 is formed of a compositionv of vulcanized rubwhich remain after theletter cutting operation protect the contiguous portions of the surface of the stone froml abrasion by thesand. After the sand blasting operation the stencil is stripped or peeled from the cut surface.

The herein described stencil-due to the material of which the sand resistant sheet 9 is formed is characterized by the fact that it is exceptionally durable and long lasting. In addition it is characterized by the fact that it-is adaptedto make extremely sharply defined letters and may be quickly and readily placed in its operative position. In view of the simplicity of its method of manufacture the stencil may be produced at a low and reasonable cost.

The invention is notto be understood as restricted to thecgdetails set forth. since these may f signs on said surface and formed of tough vulcanized rubber and an admixture 'of substantially an equai amount by weight of glueV whereby-the sheet is rendered substantially inelastic, and an `adhesive coating on the back face of the sheet for holding the sheet in adhesively connected relation withsaid surface.

2. As a new article of manufacture, a sand blasting stencil designed for use in cutting letters, symbols or designs on a surface' by way of sand blasting and comprising a santiv resistant sheet adapted to be placed against the surface and to have the desired letters, symbols or designs cut out of it, formed of vulcanized rubberand an admixture of substantially an equal amount by weight of glue whereby the sheet is rendered substantially inelastic and having a line layer of talc on the front face thereof, a coating of permanently tacky pressure sensitive adhesive applied to and covering the back face'of the sheet and adapted to hold the sheet in place with respect to said surface, and a protective sheet ofv holland covering the adhesive coating and adapted to be removed from the latter immediately before placement of the vsand resistant sheet against said surface. f

-. 3. As a new article of manufacture, a stencil `designed for use in cutting letters, symbols or designs on a surface by way of sand blasting and comprising a sand resistant sheet adapted to be placed against the surface and upon proper shaping thereof to control the sand blast so that it forms the desired letters, symbols or designs on said surface, and formed of tough vulcanized rubber and an admixture of substantially an equal amount by weight of glue whereby the sheet is rendered substantially inelastic, and a coating of permanently tacky, pressure sensitive adhesive applied to and covering the back of the sheet and adapted to hold the sheet in adhesively connected relation with said surface. y

4. As a new article of manufacture, a stencil designed for use vin cutting letters, symbols orde-gr signs on a surface'by way of sand blasting and' comprising a. sand resistant sheet adapted to/be placed against the surface and upon proper shaping thereof to control the sand blast so that it forms the desired letters, symbols or designs on said surface, and formed of tough 4vulcanized rubber, an admixture of substantially an equal amount by weight of glue whereby the sheet is rendered substantially inelastic, and a ller in greater amount than either the rubber or the glue, and an adhesive coating applied to and covering the back face of the sheet'and adapted to hold the sheet in adhesively connected relation with said surface.

` 5. As a new article of manufacture, a lstencil designed for use in cutting letters, symbols or' dedgnsonasurfacebywayofsandblastingand comprising a sand resistant sheet adapted tobel placed against the surface and upon proper shaping thereof to control the sand blast so that it forms the desired letters, symbols or designs on said surface, and formed of tough vulcanized rubber, an admixture of substantially an equal amount of glue whereby the sheet is rendered substantially inelastic, and Whiting in an amount by weight substantially equal to the combined amount of the rubber and glue, and a coating of permanently tacky pressure sensitive adhesive applied to and covering the back face offthe sheet and adapted to hold the sheet in adhesively connected relation with the surface.

6. As a new .article of manufacture, a sand blast stencil designed for use in cutting letters, symbols or designs on a surface by way of sand blasting and comprising a sand resistant sheet adapted to be placed againstthe surface and upon proper shaping thereof tocontrol the sand blast so that it forms the desired letters, symbols or symbols or designs on a surface by way of sand blasting and comprising a sand resistant sheet adapted to be placed against the surface and to have the desired letters, symbols or designs cut out. of it, and formed by spreading into layer form, and then vulcanizing, a plastic' mass including approximately 25% milled rubber, approximately 50% illler material, a small Aquantity of zinc oxide, approximately 25% glue, and extremely small quantities of petrolatum, tetram'ethylthiuram disulphide and sulfur; and a. coating of permanently tacky pressure sensitive adhesive applied to and covering the mok face of the sheet and adapted to hold the sheet in adhesively connected relation with the surface.

' 8. A stencil adapted for use in cutting letters,

symbols or designs on .a surface by way of sand' blasting and comprising a sand resistant sheet adaptedv to be placed against the surface and upon proper shaping 'thereof to controlv the sand blast so that it forms or cuts the desired letters,

symbols or' designs on said surface, provided on the back face thereof with a coextensive coating' of permanently tacky pressure sensitive adhesive for holding it in adhesively connected relation with said surface, and formed by spreading into layer form, and then vulcanizin'g, a plastic'mass including the following ingredients in substantially the specied:

aoesuag cant-nmol:

Sewanee 

